Title : Regeneration of the eye via ultrathin PDLLA-based nanofibrous membranes
Abstract:
Eye related diseases can cover diseases of the front segment of the eye as e.g. limbal stem cell deficiency (LSCD) but also diseases related to the back segment, the retina, as e.g age-related macular degeneration (AMD). In both cases one of the ways to treat the impaired part of the eye could be based on principles of tissue engineering, on suitable biodegradable scaffold combined with the cell cultivation. In this work we demonstrated, that ultrathin membrane can provide a stable substrate for cell cultivation while maintaining high optical transparency in limbal cell cultivation (1) and the same substrates can be applied subretinally to deliver retinal pigment epithelial cells to treat AMD (2). Nanofibrous membranes were prepared by electrospinning of poly(L-lactide-DL-lactide) from pyridine. This technique allows to incorporate a supporting frame. Such a frame enables not only handling without irreversible folding of the membrane and keeping a side-orientation of the sample while seeded with cells, but also to regain membrane’s flat shape during loading to the injector in subretinal surgery.
1) The fabricated scaffolds were found to successfully support the ex vivo cultivation of limbal epithelial cells (LEC). Compared to cultivation on fibrin gel, LEC cultivation on PDLLA nanofibrous scaffolds revealed heterogeneity in terms of cell expansion and morphology while maintaining similar LEC and stemness marker expression. The optical transparency of the wet PDLLA membrane could allow eyelid function and ocular surface inflammatory status control in clinical use.
2) Primary porcine RPE were cultivated on ultrathin nanofibrous membranes. The RPE monolayer showed proper differentiation, correct polarization, high phagocytic activity, good confluence and long-term survival. After implantation into subretinal space of the minipig’s eye, the minipigs were examined in postoperative period using fundus imaging and optical coherent tomography.
The ultrathin, PDLLA-based nanofibrous membranes demonstrate potential for application in the field of regenerative medicine of the eye and contribute to the development of xeno-free, highly defined, and fully standardized scaffolds.
Acknowledgments: The authors would like to thank the European Regional Development Fund (No.
CZ.02.01.01/00/22_008/0004562 Project "Excellence in Regenerative Medicine") for providing financial support.
Audience Take Away Notes:
- The novel setting of scaffolds for eye tissue engineering is presented
- Unique characteristics of nanofibrous membranes are demonstrated
- Different applications in eye-related diseases are presented
